
Operating and service manual
116 of 222 pages
Frequency Converter (FC) Alarms (AL 5XX)
For some of the alarms in this section, the FC may be faulty and must be replaced. For continuing
operation until replacement is possible, the unit can be rewired and started for emergency opera-
tion: See “Emergency Operation” p. 50.
500
FC missing
Fatal
Alarm
Description
Frequency Communication Missing
Cause
Indication of defect FC, lack of or improper connection
Trouble
shooting
Possible causes:
•
Communication with FC broken.
•
Power voltage to the FC not applied (wired for emergency operation?).
•
Defect FC.
•
X1 cable is defect.
•
Controller PCB defective.
Accompanied alarms:
•
AL 306 or one or more AL 5XX may also be active.
Trouble shooting:
1. If alarm AL 306 ‘High press switch’ is also active, the fuse F6 inside in the
control cabinet is most likely blown. Replace the fuse.
2. Verify that cable FC-com is mounted correctly according to wiring diagram
inside the controller cabinet and not being damaged.
3. Check that power to the FC is not wired for emergency operation.
4. Verify that there are correct voltages on all 3 phases for the FC.
5. Measure with a multimeter that there is a small DC signal on the connector
PCB for cable FC-com.
a) If there is no signal: The controller PCB is defective. Replace the
controller door.
b) If there is signal: The FC is defect and must be replaced. If there is no
FC replacement available, the unit can be rewired for emergency operation:
See
Emergency Operations
p.50
Criteria
Communication with FC not possible
Controller
action
Mcond, Mevap1 and Mevap2 fan motors forced to low speed
Log
X
Alarm
X
Alarm light
Quick flash
Consequence
Unit stop
Elimination
When sensor value becomes valid, it is marked as inactive in alarm list and may then be
deleted.
Log data
Parm 1
Parm 2
Parm 3
Parm 4
Parm 5
Active/Inactive Bytes Gf
Bytes Df